The amount, availability and accessibility of information in digital format continues to expand. For example, consumer electronics devices such as media players (e.g., iPod Touch), smart phones (e.g., iPhone, Blackberry, Android phone, Windows phone), tablets (e.g., iPad), computers (e.g., lap-tops, desk tops), and Interned enabled televisions may be able to access, receive, transmit, share, generate, and/or store digital information and present a semantic interpretation (visual presentation) of the digital information on a display or print the semantic interpretation. The consumer electronics devices may receive/access digital information from, for example, other consumer electronic devices networked thereto, the Internet and/or other public/private networks.
The digital information may include, for example, general information, user specific information and/or confidential information. Access to user specific information may be limited with the use of user authentication security features (e.g., user IDs and passwords). Access to confidential information may require use of secure communication channels to ensure that the digital information is not intercepted, modified and/or compromised in any fashion during transmission.
As the devices the digital information may be presented on have different parameters associated therewith, the semantic interpretation of the digital information may vary from device to device. For certain content (e.g., on-line banking information, on-line secure document viewing) it is important to ensure that the semantic interpretation of the digital information being presented on the device is not different from that which was generated on the server where the content is maintained. When a digital file is created for a document (e.g., a confidential document) a digital signature may be generated for the digital file. The validity of a digital file is authenticated by verifying that the digital signature logically matches the bit string representation of the document. The complexity of the instruments utilized for interpreting the document, creating the digital file, and producing the digital signature determines the precision with which the semantic interpretation is ensured. The ultimate goal for confidential information is to ensure that the semantic interpretation of a digitally signed file can not be changed, either by accident or by intent, this is often referred to as what you see is what you sign (WYSIWYS).
The digital files received by a device may be processed to create the semantic interpretation thereof and in cases where digital signatures are utilized to validate the digital file. The semantic interpretation may be processed and stored in graphics memory in order to present the semantic interpretation on a display thereof. The graphics memory may be randomly accessed which may enable a hacker to access the data to be presented on the display therefrom (which may include confidential information). For example, if a user is viewing their bank account information the hacker may be able to access the graphics memory to access the information being presented on their display.
In order to provide additional security encryption may be utilized. The information may be encrypted by the entity providing the information (e.g., bank server) and decrypted by the device presenting the information. The information contained in the graphics memory of the device may be the encrypted information and the graphics processor may decrypt the information so that information may be presented on the display. Electronic code book (ECB) encryption is the common encryption utilized in graphics processors as it is relatively easy to implement. However, a problem with ECB encryption is that it does a poor job of hiding patterns. ECB encryption has been sufficiently utilized to protect, for example, movies as the images presented are distorted and make the overall experience of watching the movie not enjoyable even though some of the scenes may be clearly visible.
Text within confidential information, such as banking information, encrypted using standard ECB encryption may still be visible to the human eye and/or optical character recognition (OCR) products. Accordingly, ECB encrypted confidential information may still be susceptible to a hacker accessing the information from graphics memory prior to decrypting.